Trying to find the location of the AC High Pressure Port on my 99 V70
non-Turbo.

If it exists, it is well hidden. Nothing you can do with the high pressure port anyway.

If you want to add some, use the low pressure port, in front of the left front wheel. The plastic cap has 6Mn stamped on it - meaning 'finger tight'.
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Keeping it running is better than buying new

Replaced the bearing on the AC clutch, I had to remove the compressor. I have a vacuum pump and wanted to pull the proper vacuum. I have replaced the bearing on my other car and did it while it was installed, real pain. I connected the vacuum to the low pressure side and let it run for 40 Min.
Put in the proper amount of AC Stuff and it seems to blow cool. I left the vacuum gauge on and shut the pump of for 1 hr before I put the cool stuff in and it held vacuum so I don't think I have any leaks. Any way if the compressor fails no big deal as long as the clutch spins free, my 17 yr old son can go without AC, Like I did when i was his age.